EP0139230A2 - Floating capacitor simulation circuit - Google Patents

Floating capacitor simulation circuit Download PDF

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Publication number
EP0139230A2
EP0139230A2 EP84111226A EP84111226A EP0139230A2 EP 0139230 A2 EP0139230 A2 EP 0139230A2 EP 84111226 A EP84111226 A EP 84111226A EP 84111226 A EP84111226 A EP 84111226A EP 0139230 A2 EP0139230 A2 EP 0139230A2
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EP
European Patent Office
Prior art keywords
resistor
capacitive
impedance
complex
voltage divider
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Granted
Application number
EP84111226A
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German (de)
French (fr)
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EP0139230B1 (en
EP0139230A3 (en
Inventor
Benno Dreier
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Alcatel Lucent Deutschland AG
Alcatel Lucent NV
Original Assignee
Alcatel SEL AG
Standard Elektrik Lorenz AG
Alcatel NV
International Standard Electric Corp
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Publication of EP0139230A2 publication Critical patent/EP0139230A2/en
Publication of EP0139230A3 publication Critical patent/EP0139230A3/en
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Publication of EP0139230B1 publication Critical patent/EP0139230B1/en
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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H11/00—Networks using active elements
    • H03H11/02—Multiple-port networks
    • H03H11/28—Impedance matching networks
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H11/00—Networks using active elements
    • H03H11/46—One-port networks
    • H03H11/48—One-port networks simulating reactances
    • H03H11/483—Simulating capacitance multipliers

Definitions

  • the invention relates to a capacitive, complex resistor.
  • An advantage of the capacitive, complex resistor according to the invention lies in the fact that this circuit can be used potential-free as a pure two-pole, which transmits an AC signal in both directions, the same complex total impedance being effective in both transmission directions.
  • a PoL E of a capacitive, complex two-pole impedance in FIG. 1 is connected to a resistor R2 and is led to the other PoL A via a series impedance ZO, which consists of a parallel RC element RO, CO.
  • the impedance value Z results in
  • FIG. 2 shows a capacitive, complex impedance Z which, according to the invention, has a capacitive impedance Z3 which lies in series with an ohmic resistor R1 which is bridged by a voltage follower circuit SFS .

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  • Networks Using Active Elements (AREA)
  • Oscillators With Electromechanical Resonators (AREA)
  • Electrotherapy Devices (AREA)
  • Filters And Equalizers (AREA)
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  • Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
  • Materials For Medical Uses (AREA)
  • Organic Insulating Materials (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
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Abstract

A complex capacitive impedance (Z) whose capacitance value is considerably larger than the total capacitance of the components used in it is implemented by connecting a capacitive impedance (Z3) in series with a first resistor (R1) to form a voltage divider, and bypassing the first resistor (R1) with a voltage follower circuit (SFS).

Description

Die Erfindung betrifft einen kapazitiven, komplexen Widerstand.The invention relates to a capacitive, complex resistor.

In vielen Anwendungsgebieten, inbesondere bei integrierten SchaLtkreisen, besteht die technische Aufgabe, kapazitive Impedanzen so nachzubilden, daß der Kapazitätswert des tatsächlich eingesetzten Kondensators wesentlich geringer ist als die Gesamtkapazität der nach außen wirksam erscheinenden Impedanz..In many fields of application, in particular with integrated circuits, the technical task is to simulate capacitive impedances in such a way that the capacitance value of the capacitor actually used is considerably less than the total capacitance of the impedance which appears to be effective to the outside.

Zur Erzeugung solcher Impedanzen sind KapazitätsmuLtipLizierer bekannt (z.B. US-PS 3 831 117). Ein solcher weist einen DifferentiaLverstärker auf, dessen erster Eingang über einen ersten Widerstand mit einem Eingang der SchaLtungsanordnung und dessen zweiter Eingang über einen zweiten Widerstand mit dem Ausgang des DifferentiaLverstärkers verbunden ist. Der DifferentiaLverstärkerausgang ist über einen dritten Widerstand an den Eingang der SchaLtungsanordnung angeschlossen. Ferner ist die eine Kapazität enthaltende Impedanz einerseits an den ersten Eingang des DifferentiaLverstärkers und andererseits an ein festes BezugspotentiaL, üblicherweise das Erdpotential, der SchaLtungsanordnung geschaltet. Der Kapazitätsmultiplizierer stellt somit einen VierpoL dar, wobei das kapazitive BaueLement notwendigerweise im Querzweig zum SignaLfLuß an festem Potential Liegt.Capacitance multiplicators are known for generating such impedances (for example US Pat. No. 3,831,117). Such has a differential amplifier, the first input of which is connected via a first resistor to an input of the circuit arrangement and the second input of which is connected to the output of the differential amplifier via a second resistor. The differential amplifier output is connected to the input of the circuit arrangement via a third resistor. Furthermore, the impedance containing a capacitance is on the one hand at the first Input of the differential amplifier and on the other hand connected to a fixed reference potential, usually the earth potential, of the circuit arrangement. The capacity multiplier thus represents a four-pole, with the capacitive component necessarily lying in the transverse branch to the signal flow at a fixed potential.

Kapazitive, komplexe Impedanzen, die als potentialfreie ZweipoLe verwendbar sind, d.h. über die üblicherweise ein Wechselstromsignal in beiden Richtungen bei jeweils gleicher Gesamtimpedanz übertragen werden soll, können nicht mit HiLfe dieser, mit festem Potential verbundenen Kapazitätsmultiplizierer realisiert werden.Capacitive, complex impedances that can be used as potential-free two-pole, i.e. With the help of which an alternating current signal is usually to be transmitted in both directions with the same total impedance in each case, these capacitance multipliers, which are connected to a fixed potential, cannot be implemented with the help.

Die oben genannte technische Aufgabe wird erfindungsgemäß durch die MerkmaLe des Patentanspruchs 1 gelöst.The above-mentioned technical problem is solved according to the invention by the features of patent claim 1.

Ein Vorteil des kapazitiven, komplexen Widerstands nach der Erfindung, Liegt darin, daß diese SchaLtung potentialfrei als reiner ZweipoL eingesetzt werden kann, der ein Wechselstromsignal in beiden Richtungen überträgt, wobei in beiden übertragungsrichtungen die gleiche komplexe Gesamtimpedanz wirksam ist.An advantage of the capacitive, complex resistor according to the invention lies in the fact that this circuit can be used potential-free as a pure two-pole, which transmits an AC signal in both directions, the same complex total impedance being effective in both transmission directions.

VorteiLhafte WeiterbiLdungen der Erfindung sind in den Unteransprüchen angegeben.Advantageous further developments of the invention are specified in the subclaims.

Zwei AusführungsbeispieLe werden im folgenden anhand der Zeichnungen näher erläutert. Es zeigen:

  • Figur 1 eine übliche SchaLtungsanordnung einer komplexen, kapazitiven Impedanz
  • Figur 2 ein BLockschaLtbiLd des kapazitiven, komplexen Widerstands Z nach der Erfindung
  • Figur 3 eine erste ausführliche DarsteLLung für einen kapazitiven, komplexen Widerstand nach der Erfindung
  • Figur 4 eine zweite ausführliche DarsteLLung für einen kapazitiven, komplexen Widerstand nach der Erfindung.
Two exemplary embodiments are explained in more detail below with reference to the drawings. Show it:
  • 1 shows a conventional circuit arrangement of a complex, capacitive impedance
  • Figure 2 is a BLockschaLtBild of capacitive, complex resistor Z according to the invention
  • Figure 3 is a first detailed illustration of a capacitive, complex resistor according to the invention
  • FIG. 4 shows a second detailed illustration for a capacitive, complex resistor according to the invention.

Ein PoL E einer kapazitiven, komplexen Zweipolimpedanz in Figur 1 ist mit einem Widerstand R2 verbunden und über eine in Reihe Liegende Impedanz ZO, die aus einem Parallel-RC-GLied RO, CO besteht, an den anderen PoL A geführt. Der Impedanzwert Z ergibt sich zu

Figure imgb0001
A PoL E of a capacitive, complex two-pole impedance in FIG. 1 is connected to a resistor R2 and is led to the other PoL A via a series impedance ZO, which consists of a parallel RC element RO, CO. The impedance value Z results in
Figure imgb0001

Das BLockschaLtbiLd in Figur 2 zeigt eine kapazitive, komplexe Impedanz Z, die gemäß der Erfindung eine kapazitive Impedanz Z3 aufweist, die in Reihe mit einem ohmschen Widerstand R1 Liegt, welcher von einer Spannungsfolgerschal- tung SFS überbrückt ist.The block circuit diagram in FIG. 2 shows a capacitive, complex impedance Z which, according to the invention, has a capacitive impedance Z3 which lies in series with an ohmic resistor R1 which is bridged by a voltage follower circuit SFS .

Die Figur 3 zeigt ein erstes detaiLiertes Ausführungsbeispiel.Figure 3 shows a first detailed embodiment.

Ein PoL A ist mit einer Impedanz Z3, die aus der ParaLLeLschaltung eines Widerstandes R3 und eines Kondensators C3 besteht, verbunden. Die Impedanz Z3 bildet mit einem Widerstand R1 einen SpannungsteiLer, dessen MitteLabgriff G mit dem nichtinvertierenden Eingang eines als SpannungsfoLger geschalteten Operationsverstärkers OP1 verbunden ist. Der Ausgang F des Operationsverstärkers OP1 ist über den Widerstand R2 mit dem anderen PoL E und der dem Mittelabgriff G abgewandten Seite des Widerstandes R1 verbunden. Gibt man dem Widerstand R1 und der Impedanz Z3 die Werte

Figure imgb0002
Figure imgb0003
so ergeben sich für R3 und C3 die Werte
Figure imgb0004
Figure imgb0005
 A PoL A is connected to an impedance Z3, which consists of the parallel circuit of a resistor R3 and a capacitor C3. The impedance Z3 forms a voltage divider with a resistor R1, the center tap G of which is connected to the non-inverting input of an operational amplifier OP1 connected as a voltage feeder. The output F of the operational amplifier OP1 is connected via the resistor R2 to the other PoL E and the side of the resistor R1 facing away from the center tap G. If the values are given to resistor R1 and impedance Z3
Figure imgb0002
Figure imgb0003
 this gives the values for R3 and C3
Figure imgb0004
Figure imgb0005

Um ein möglichst großes Verhältnis von Impedanzkapazität zur Kapazität der eingesetzten kapazitiven BaueLemente zu erreichen, wird de.r faktor K recht groß, beispielsweise K = 100 gewählt. Damit ist der Widerstand R1 wesentlich größer als der Widerstand R2 und der Strom IN gegenüber dem Strom IE vernachlässigbar. Die Berechnung der komplexen, kapazitiven Impedanz vereinfacht sich hierdurch erheblich. Für die Impedanz Z gilt

Figure imgb0006
wobei
Figure imgb0007
und das Spannungsteilerverhältnis
Figure imgb0008
eingesetzt in (6) für Z den Wert
Figure imgb0009
ergibt.In order to achieve the largest possible ratio of impedance capacity to the capacitance of the capacitive components used, the factor K is chosen to be quite large, for example K = 100. Resistor R1 is thus significantly larger than resistor R2 and current IN is negligible compared to current I E. This considerably simplifies the calculation of the complex, capacitive impedance. The following applies to the impedance Z.
Figure imgb0006
 in which
Figure imgb0007
 and the voltage divider ratio
Figure imgb0008
 used in (6) for Z the value
Figure imgb0009
 results.

Der in der SchaLtungsanordnung nach Figur 1 vorgegebene Impedanzwert Z wird durch die erfindungsgemäße Anordnung nicht verändert. Verändert hat sich aber der Wert der erforderLichen, durch ein BaueLement zu bildenden Kapazität, die jetzt den Wert

Figure imgb0010
annimmt, was bei einem großen Faktor K einer wesentlichen VerkLeinerung der ursprünglichen Kapazität CO entspricht.The impedance value Z specified in the circuit arrangement according to FIG. 1 is not changed by the arrangement according to the invention. However, the value of the required capacity to be formed by a building element has changed, which is now the value
Figure imgb0010
 assumes what corresponds to a substantial reduction in the original capacitance CO with a large factor K.

Für die Berechung sind nahezu ausschließlich große Faktoren K von Interesse, da die verwendeten kapazitiven BaueLemente möglichst kleine Kapazitätswerte haben sollten, um eine Ausführung der komplexen, kapazitiven Impedanz Z als integrierte Schaltung zu ermöglichen.Almost exclusively large factors K are of interest for the calculation, since the capacitive components used should have the smallest possible capacitance values in order to enable the complex, capacitive impedance Z to be implemented as an integrated circuit.

Ein zweites AusführungsbeispieL ist in Figur 4 angegeben. Hier ist anstatt des gesamten Widerstandes R1 des Spannungsteilers nur ein Teilbetrag des Widerstandes R1 der in Figur 4 als Widerstand R1' dargestellt ist, mit der SpannungsfoLgerschaLtung SFS überbrückt. Dieser fehlende Betrag des Widerstandes R1 wird als Widerstand R4 in der Impedanz Z3 in Reihe mit dem Parallel-RC-Glied C3, R3 geschaltet. Damit sich nun der Gesamtwert der kompLexen, kapazitiven Impedanz Z nicht verändert, und der Widerstand R2 nach (2) und (3) um den Betrag des Widerstandes R4 verkLeinert. Dies ergibt einen tatsächlich kleineren Ausgangswiderstand R5 der SchaLtung bei einer sich gleichzeitig nicht verändernden Gesamtimpedanz Z. Eine solche Schaltungsvariante kann vorteilhaft eingesetzt werden, wenn ein kleinerer Ausgangswiderstand R5 des Operationsverstärkers OP1 erwünscht ist.A second exemplary embodiment is given in FIG. 4. Here, instead of the entire resistor R1 of the voltage divider, only a partial amount of the resistor R1, which is shown in FIG. 4 as the resistor R1 ', is bridged with the voltage follower circuit SFS. This missing amount of the resistor R1 is connected as a resistor R4 in the impedance Z3 in series with the parallel RC element C3, R3. So that the total value of the complex, capacitive impedance Z not changed, and the resistance R2 according to (2) and (3) decreased by the amount of the resistance R4. This results in an actually lower output resistance R5 of the circuit with a total impedance Z which does not change at the same time. Such a circuit variant can be used advantageously if a smaller output resistance R5 of the operational amplifier OP1 is desired.

Claims (4)

1. Kapazitiver, komplexer Widerstand, dadurch gekennzeichnet , daß eine eine Kapazität enthaltende Impedanz (Z3) in Reihe mit einem ersten ohmschen Widerstand (R1) einen Spannungsteiler bildet, und daß der erste ohmsche Widerstand (R1) durch eine SpannungsfoLgerschaltung (SFS) überbrückt ist.1. Capacitive, complex resistor, characterized in that an impedance containing a capacitance (Z3) forms a voltage divider in series with a first ohmic resistor (R1), and that the first ohmic resistor (R1) is bridged by a voltage supply circuit (SFS) . 2. Kapazitiver, komplexer Widerstand nach Anspruch 1, dadurch gekennzeichnet, daß die Spannungsfolgerschaltung (SFS) aus einem als Spannungsfolger beschalteten Operationsverstärker (OP1) besteht, dessen Ausgang (F) ein zweiter ohmscher Widerstand (R2) vorgeschaltet ist, und daß der zweite ohmsche Widerstand (R2) einen wesentlich kleineren Wert als der erste ohmsche Widerstand (R1) des SpannungsteiLers besitzt.2. Capacitive, complex resistor according to claim 1, characterized in that the voltage follower circuit (SFS) consists of an operational amplifier (OP1) connected as a voltage follower, the output (F) of which is connected upstream of a second ohmic resistor (R2), and that the second ohmic Resistor (R2) has a much smaller value than the first ohmic resistor (R1) of the voltage divider. 3. Kapazitiver, komplexer Widerstand nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die kapazitive Impedanz (Z3) des Spannungsteilers aus einer Parallelschaltung eines dritten ohmschen Widerstands (R3) und eines Kondensators (C3) besteht.3. Capacitive, complex resistor according to claim 1 or 2, characterized in that the capacitive impedance (Z3) of the voltage divider consists of a parallel connection of a third ohmic resistor (R3) and a capacitor (C3). 4. Kapazitiver, komplexer Widerstand nach einem der vorherigen Ansprüche, dadurch gekennzeichnet, daß die kapazitive Impedanz (Z3) des SpannungsteiLers aus einer Parallelschaltung des dritten Widerstandes (R3) und des Kon- densators (C3) besteht, der ein vierter Widerstand (R4) in Reihe geschaltet ist.4. Capacitive, complex resistance according to any one of the preceding claims, characterized in that the capacitive impedance (Z3) of the voltage divider n of a parallel connection of the third resistor (R3) and the co - densators (C3) consists of a fourth resistor (R4 ) is connected in series.
EP84111226A 1983-09-22 1984-09-20 Floating capacitor simulation circuit Expired EP0139230B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19833334243 DE3334243A1 (en) 1983-09-22 1983-09-22 CAPACITIVE, COMPLEX RESISTANCE
DE3334243 1983-09-22

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EP0139230A2 true EP0139230A2 (en) 1985-05-02
EP0139230A3 EP0139230A3 (en) 1985-12-11
EP0139230B1 EP0139230B1 (en) 1988-06-22

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EP84111226A Expired EP0139230B1 (en) 1983-09-22 1984-09-20 Floating capacitor simulation circuit

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EP (1) EP0139230B1 (en)
JP (1) JPS60172811A (en)
KR (1) KR850002711A (en)
AT (1) ATE35353T1 (en)
AU (1) AU567972B2 (en)
BR (1) BR8404601A (en)
CA (1) CA1226631A (en)
CS (1) CS271308B2 (en)
DD (1) DD223880A5 (en)
DE (2) DE3334243A1 (en)
EG (1) EG17005A (en)
ES (1) ES536155A0 (en)
GR (1) GR80396B (en)
HU (1) HU189431B (en)
IN (1) IN162335B (en)
MA (1) MA20234A1 (en)
NO (1) NO843684L (en)
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PL (1) PL249558A1 (en)
PT (1) PT79226B (en)
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0450866A2 (en) * 1990-04-03 1991-10-09 Pilkington Micro-Electronics Limited Semiconductor capacitor circuit
EP0485926A2 (en) * 1990-11-15 1992-05-20 STMicroelectronics S.r.l. Constant-absorption circuit for the bidirectional transfer of an alternating signal
EP0610066A1 (en) * 1993-02-04 1994-08-10 National Semiconductor Corporation Capacitance multiplier for the internal frequency compensation of switching regulator integrated circuits
GB2284956A (en) * 1993-12-14 1995-06-21 Texas Instruments Ltd An active capacitor network

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3334243A1 (en) * 1983-09-22 1985-04-04 Standard Elektrik Lorenz Ag, 7000 Stuttgart CAPACITIVE, COMPLEX RESISTANCE
EP0398897A1 (en) * 1988-12-05 1990-11-28 BELL TELEPHONE MANUFACTURING COMPANY Naamloze Vennootschap Voltage transducer
US5420495A (en) * 1993-04-19 1995-05-30 Electric Power Research Institute, Inc. Transmission line power flow controller
US5760728A (en) * 1997-02-03 1998-06-02 Motorola, Inc. Input stage for an analog-to-digital converter and method of operation thereof
EP2451077B1 (en) 2010-11-03 2013-06-19 Nxp B.V. Integrated circuit capacitor

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2691106A (en) * 1945-09-27 1954-10-05 Roger B Woodbury Variable reactance electron tube circuit
US3243740A (en) * 1960-10-20 1966-03-29 Westinghouse Electric Corp Reactance enhancing networks
US3831117A (en) * 1972-11-15 1974-08-20 Nasa Capacitance multiplier and filter synthesizing network
GB1413722A (en) * 1973-01-17 1975-11-12 Post Office Filter networks
US4025867A (en) * 1976-06-16 1977-05-24 Bell Telephone Laboratories, Incorporated Capacitance magnification circuit
DE2655320B2 (en) * 1976-12-07 1979-02-01 Te Ka De Felten & Guilleaume Fernmeldeanlagen Gmbh, 8500 Nuernberg Controllable electronic resistance
US4424499A (en) * 1980-02-11 1984-01-03 Reliance Electric Company Equalizer circuit for a repeater
DE3009118A1 (en) * 1980-03-10 1981-09-17 Ephraim 8541 Büchenbach Jackson Circuit which simulates inductance - using single operational amplifier and seven impedances of various types
JPS58120317A (en) * 1982-01-13 1983-07-18 Toshiba Corp Variable output impedance circuit
US4532384A (en) * 1983-02-04 1985-07-30 Northern Telecom Limited Line feed circuit including negative impedance circuit
DE3334243A1 (en) * 1983-09-22 1985-04-04 Standard Elektrik Lorenz Ag, 7000 Stuttgart CAPACITIVE, COMPLEX RESISTANCE

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ELECTRONICS LETTERS, Band 15, Nr. 21, Oktober 1979, Seiten 688-689, London, GB; D. PATRANABIS et al.: "Novel capacitor floatation scheme" *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0450866A2 (en) * 1990-04-03 1991-10-09 Pilkington Micro-Electronics Limited Semiconductor capacitor circuit
EP0450866A3 (en) * 1990-04-03 1992-01-02 Pilkington Micro-Electronics Limited Semiconductor capacitor circuit
EP0485926A2 (en) * 1990-11-15 1992-05-20 STMicroelectronics S.r.l. Constant-absorption circuit for the bidirectional transfer of an alternating signal
EP0485926A3 (en) * 1990-11-15 1993-06-09 Sgs-Thomson Microelectronics S.R.L. Constant-absorption circuit for the bidirectional transfer of an alternating signal
EP0610066A1 (en) * 1993-02-04 1994-08-10 National Semiconductor Corporation Capacitance multiplier for the internal frequency compensation of switching regulator integrated circuits
US5382918A (en) * 1993-02-04 1995-01-17 National Semiconductor Corporation Capacitance multiplier for the internal frequency compensation of switching regulator integrated circuits
GB2284956A (en) * 1993-12-14 1995-06-21 Texas Instruments Ltd An active capacitor network
GB2284956B (en) * 1993-12-14 1997-09-03 Texas Instruments Ltd An active capacitor network

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YU45664B (en) 1992-07-20
NO843684L (en) 1985-03-25
CA1226631A (en) 1987-09-08
MA20234A1 (en) 1985-04-01
GR80396B (en) 1985-01-17
EP0139230B1 (en) 1988-06-22
CS710184A2 (en) 1990-02-12
BR8404601A (en) 1985-08-06
DE3334243A1 (en) 1985-04-04
YU163284A (en) 1987-02-28
IN162335B (en) 1988-04-30
AU3323284A (en) 1985-03-28
EG17005A (en) 1990-06-30
PT79226B (en) 1986-08-22
US4607243A (en) 1986-08-19
ZA846891B (en) 1985-04-24
HU189431B (en) 1986-07-28
PL249558A1 (en) 1985-06-04
HUT36301A (en) 1985-08-28
NZ209464A (en) 1988-01-08
EP0139230A3 (en) 1985-12-11
TR22029A (en) 1986-01-27
CS271308B2 (en) 1990-09-12
RO91278B (en) 1987-05-01
DE3472340D1 (en) 1988-07-28
ES8604372A1 (en) 1985-12-16
DD223880A5 (en) 1985-06-19
RO91278A (en) 1987-04-30
JPS60172811A (en) 1985-09-06
KR850002711A (en) 1985-05-15
PH20792A (en) 1987-04-14
AU567972B2 (en) 1987-12-10
ATE35353T1 (en) 1988-07-15
PT79226A (en) 1984-10-01
ES536155A0 (en) 1985-12-16

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